Used plastic is always left as plastic waste. Some of them are reused in different ways whereas some are disposed by different methods. Landfills is one of the convenient method, however, it affects the environment as plastic is difficult to degenerate. Thus, they are piled up in the soil and the amount is increasing everyday because of the increasing use of plastic. Burning plastic waste cause pollution and hazard.
*** The most effective solution to plastic waste problem is to recycle them.***
There are many to recycle plastic waste.
Used plastic products such as bowls, plates, glass, bottles, and some containers can be cleaned before reuse. However, the quality and beauty of these containers may degenerate. Moreover, cleanliness and safety are the top concern.
To reuse the plastic waste by fusion is very popular. However, comparing to the entire amount of plastic waste, this is only a few part because of the lower quality of plastic. Moreover, it requires the mixture of new plastic in the appropriate ratio.
Use as fuel
Most of thermoplastic are flammable and ignited so it can be used as fuel directly.
Use as composite material
Mix plastic waste with other materials to produce new useful composite material such as artificial wood and artificial marble. These product might not have high quality.
Transform to liquid and gas product
Changing plastic waste into liquid and gas products is the method to obtain hydrocarbon in form of liquid and gas or the mixture of many types of hydrocarbon which may be used as the fuel directly or distill to pure substance as the raw material in plastic resin production, as same as the raw material from petroleum. This process gives high quality plastic resin. The method of changing used plastic into liquid is called liquefaction; pyrolysis with extreme heat under nitrogen atmosphere or other inert gas. Apart from liquid, the by-product is carbon waste which is solid substance that can be fuel. Gas obtained from pyrolysis process is hydrocarbon which is the fuel as well. Beside, there are other gas obtained such as hydrogen chloride that is useful in some industries.